NIS Upgrade on Vista 64-bit

Hi,

 

I'm due to renew my NIS in 10 days. I'm thinking I should upgrade. I know I didn't upgrade last year -- I just renewed. I'm running NIS 2011 or 2012 (how do I tell?) on a Vista Home Premium 64-bit system with Internet Explorer 8.

 

Since I've seen problems posted here on NIS 2014 that I don't want to deal with, how do I upgrade to NIS 2013? Is 2013 compatible with my system?

 

Thank you.